21.

Boron cannot form which one of the following anions?

• BF₆^3-

• BH₄^-

• B(OH)₄^-

• B(OH)₄^-

The degree of dissociation (α) of a weak electrolyte ,A_xB_y is related to van't Hoff factor (i) by the expression

The presence or absence of hydroxy group on which carbon atom of sugar differentiates RNA and DNA.

• 1st

• 2nd

• 3rd

• 3rd

Phenol is heated with a solution of a mixture of KBr and KBrO₃.The major product obtained in the above reaction is

• 2-Bromophenol

• 3-Bromophenol

• 4-Bromophenol

• 4-Bromophenol

Which of the following reagents may be used to distinguish between phenol and benzoic acid ?

• Aqueous NaOH

• Tollen's reagent

• Molisch reagent

• Molisch reagent

Trichloroacetaldehyde was subjected to Cannizzaro's reaction by using NaOH. The mixture of the products contains sodium trichloroacetate ion and another compound. The other compound is

• 2, 2, 2-Trichloroethanol

• Trichloromethanol

• 2, 2, 2-Trichloropropanol

• 2, 2, 2-Trichloropropanol

The strongest acid amongst the following compounds is

• CH₃COOH

• HCOOH

• CH₃CH₂CH(Cl)CO₂H

• CH₃CH₂CH(Cl)CO₂H

Ozonolysis of an organic compound gives formaldehyde as one of the products. This confirms the presence of,

• two ethylenic double bonds

• a vinyl group

• an isopropyl group 

• an isopropyl group 

Sodium ethoxide has reacted with ethanoyl chloride. The compound that is produced in the above reaction is

• Diethyl ether

• 2-Butanone

• Ethyl chloride

• Ethyl chloride

Silver Mirror test is given by which one of the following compounds?

• Acetaldehyde

• Acetone

• Formaldehyde

• Formaldehyde